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#ifndef SRC_TINT_LANG_WGSL_AST_TRANSFORM_DEMOTE_TO_HELPER_H_
#define SRC_TINT_LANG_WGSL_AST_TRANSFORM_DEMOTE_TO_HELPER_H_
#include "src/tint/lang/wgsl/ast/transform/transform.h"
namespace tint::ast::transform {
/// Implement demote-to-helper semantics for discard statements.
///
/// For backend targets that implement discard by terminating the invocation, we need to change the
/// program to ensure that discarding the fragment does not affect uniformity with respect to
/// derivative operations. We do this by setting a global flag and masking all writes to storage
/// buffers and textures.
///
/// @note Depends on the following transforms to have been run first:
/// * PromoteSideEffectsToDecl
/// * ExpandCompoundAssignment
class DemoteToHelper final : public Castable<DemoteToHelper, Transform> {
public:
/// Constructor
DemoteToHelper();
/// Destructor
~DemoteToHelper() override;
/// @copydoc Transform::Apply
ApplyResult Apply(const Program& program,
const DataMap& inputs,
DataMap& outputs) const override;
};
} // namespace tint::ast::transform
#endif // SRC_TINT_LANG_WGSL_AST_TRANSFORM_DEMOTE_TO_HELPER_H_